It's been shown that characters (like Hank Pym, Bill Foster, and Stature) who've had repeated and prolonged exposure to the Pym Particles have internalized their capabilities. Why hasn't this happened with Scott Lang?

Janet was a firestarter, but only demonstrated her uncontrollable powers once, so not much more is known than that.

Hit-Monkey's intelligence is not a mutation. He demonstrated a similar level of intelligence to the other members of his people in his origin story.

Ricky Meyers is roughly old enough to be born before or after Samson was irradiated. It's too close to call without further information.

@Dr.House:

I honestly thought it had, although recent stories have shown him relying on equipment. It's possible he relies upon a different formula of Pym Particles designed to be more stable than Hank's, but preventing long term bonding under normal conditions. But that's speculation.

"If you want to tell people the truth, make them laugh, otherwise they'll kill you." -- Oscar Wilde

Space: allows you to be anywhere at once. It's most famous application is the power to teleport anywhere you want, even to alternate realities. Time: allows you to travel through time, see the past, view future timelines, speed up or slow down time itself. Mind: connects every mind in the universe, making you the most powerfull omnipath there is. It holds every psychic power like telepathy, telekineses, illusioncasting etc. Reality: allows you to rewrite the laws of physics, making your every dream, fantasy etc. to come true.Power: an infinite powersource that will grant you every superhuman ability there is, like superstrength, durability, flight, energy manipulation etc. Also used to power machines or amplify the power of the other stones.Soul: vampiric in nature, even to the wielder itself, holds a pocketdimension where it stores the soul of it's victims. It can connect all other stones. Mastery of the stone would allow the user to control all living life in the universe.

While each stone in itself is insanely powerfull, put them together and you'll be literaly a god; able to do whatever you want.

When wielded separately, the power of the Gems varies from user to user, depending on what they are capable of tapping into. The Infinity Gems are linked to each other mentally. Supposedly, this is because the Gems were the remnant of the previous supreme being of the universe (Galactus's origin universe), although how that ties into the recent revelations from Ultimates 2 is unclear. Anyone who has wielded the Gems in the past remains linked to them in some way, possessing a form of cosmic awareness derived from having been tied into a greater infinity. For instance, Thanos was once able to send a telepathic call to Nebula, which was intercepted by Gamora, all because of their previous wielding of the Gems.

The Soul Gem was introduced first, in the possession of the High Evolutionary when he passed it on to Adam Warlock. It had a unique interaction with Adam's own cosmic powers. Basically, Adam was TOO powerful on his own, and his abilities were burning his body out (think early Nate Grey). To compensate, he limited his powers to their minimal levels but focused them through the Soul Gem, which was fed by spiritual energy: his own confidence, and the faith that others had in him. The Soul Gem had an unexplained vampiric nature, though, causing it and Adam to hunger for the souls of others. It also coaxed most of Adam's soul into itself, leaving him unable to remove it. The scenario flipped, and Adam began spending most of his energies on containing the Soul Gem's appetites, rather than using it to enhance his powers. In later years, Adam learned to use the Soul Gem to fire karmic blasts, disrupting the soul rather than taking it. Others have wielded the Soul Gem like the In-Betweener and Rune, the later of whom's natural vampiric abilities were drastically exaggerated by the Gem.

The Power Gem has infinite raw power that can be directed for devastating effect, or harnessed to augment any given system. Wielders such as Champion, Thor, Drax, and Titania have used it to achieve literally immeasurable strength, with their physical power levels constrained only by their imaginations.

The Time Gem can be manipulated for time travel, viewing the past and future, altering the flow of time on specific people or objects, etc. Gamora harnessed the Time Gem only minimally, gaining a form of precognitive sight to anticipate and counter her opponents in battle, or unbidden visions of the future that alerted her to potential dangers. The Gardener wielded the Gem in his garden, accelerating plant growth and maintaining his flowers at the apex of their bloom.

The Mind Gem grants mental powers or boosts existing ones. This was the Gem Moondragon used, amplifying her moderate telepathic and telekinetic abilities to Phoenix levels, allowing her to rearrange molecular structures, even creating a working starship by assembling molecules from the soil around her. In the Ultraverse, the Mind Gem turned the bestial creature known as Primevil into a coherent, educated, and intelligent being.

The Reality Gem is the most difficult gem to wield individually. Like the power of Proteus or Disassembled era Scarlet Witch, it can alter reality itself, manifesting whims, reconstructing universal laws, dimensional structure, and so on. The sensory input provided from Space, Time, Soul, and Mind is often necessary to understand and control the power of the Reality Gem, causing minds to lose themselves if they attempt to wield it alone. Loki and Night Man had an encounter over the Reality Gem where Night Man's every move or decision caused him to split off a doppelganger, causing him to manifest every possible outcome of a situation in a single timeline. Recently, Carol Danvers recovered the Reality Gem in another reality, indicating the rules of the Infinity Gems may have changed, since typically the Gems can only operate in their own native reality.

The Space Gem reduces the idea of distance to a mere concept, allowing the wielder to be anywhere they choose to be. Often this appears in the form of teleportation. Pip the Troll was given permanent teleportation powers from his time with the Space Gem. The Elder known as the Runner subliminally tapped into the gem's power, believing it was making him faster as he ran. In fact, it was bending space between him and his destinations.

The sentient A.I. core of the Celestial Ship was smaller than a basketball. The Celestial Ship itself was capable of technoforming itself, changing its internal or external structure to match the needs of the passengers, or Ship itself. Implanted in Cable's body, the Professor acted like a cybernetic interface. It was linked to various sensor systems, could monitor Nate's vital signs and power levels, and access any other tech Cable had incorporated into his techno-organics, including the bodyslide equipment. As Prosh, the Professor had assimilated and bonded with a Phalanx drone, receiving the basic capabilities of that species as well.

The full capabilities of Mjolnir, Stormbreaker, and Thunderstrike can be found on the Thor post in the Archives. Suffice it to say, Stormbreaker was created to give Beta Ray Bill access to all the powers of Thor. Odin removed the enchantment allowing Thor to become Don Blake and placed it on Stormbreaker, enabling Bill to change back to his original, non-cybernetic Corbinite form. The mace known as Thunderstrike also duplicated most of Mjolnir's capabilities so that Eric Masterson could operate as Thunderstrike alongside Thor. Thunderstrike's primary enchantment was the "thunder blasts" fired from the head of the mace. It maintained the spells of worthiness, transformation, flight, and returning to his grasp that Mjolnir did. Thunderstrike very occasionally used his mace for teleportation or weather control, but didn't seem to have a good grasp on these abilities with Mjolnir and the spirit of Thor to help guide him.

"If you want to tell people the truth, make them laugh, otherwise they'll kill you." -- Oscar Wilde

Epsilon Red was designed as a super-cosmonaut to parallel Omega Red's super-soldier. His body was engineered to survive and thrive in vacuum instead of planetside. He had four bionic and prehensile coils extending from his body (backpack?), equipped with what appeared to be tools to assist in engineering or maintenance in a zero-G environment. He was reportedly a telepath, although the twist in his original storyline was that it was actually his daughter Elena who was the telepath. His recent appearance in Tales of Suspense, however, indicated he also possessed that power.

"If you want to tell people the truth, make them laugh, otherwise they'll kill you." -- Oscar Wilde

Omega Red was both, so it's possible Epsilon Red was as well. It's also possible to be a psychic without being a mutant. It hasn't been clarified either way.

Even before Claremont stopped writing her, Psylocke's "immunity" was slipping. She was mind-controlled in New Exiles, for instance. I imagine Jamie's initial efforts simply wore off over time, but no explicit mention of it was ever made.

"If you want to tell people the truth, make them laugh, otherwise they'll kill you." -- Oscar Wilde

Omega Red was both, so it's possible Epsilon Red was as well. It's also possible to be a psychic without being a mutant. It hasn't been clarified either way.

Even before Claremont stopped writing her, Psylocke's "immunity" was slipping. She was mind-controlled in New Exiles, for instance. I imagine Jamie's initial efforts simply wore off over time, but no explicit mention of it was ever made.

I'm not sure this would count as reality alteration, but didn't Proteus strip the flesh from her hand on Muir Island during Necorsha?

Never worry what other people think of you, because no one ever thinks of you.

Many people who had got to know Rincewind had come to treat him as a sort of two-legged miner's canary, and tended to assume that if Rincewind was still upright and not actually running then some hope remained.